Recently telecommunication has made considerable progress. A part of this progress manifests in the fact that a user may access different networks from a single terminal device such as a mobile station MS, and transmit/receive different kinds of data from/with said terminal.
For example, a considerable progress represents the possibility to access the Internet from one's mobile station and to perform data transfer between the Internet and one's mobile station.
Such data transfers rely on packet data transmission, according to which data are transmitted in units of packets. An example for a packet data network enabling such a packet data transmission is the GPRS network GPRS-NW roughly illustrated in FIG. 1. (GPRS=General Packet Radio Service) for explanatory purposes. FIG. 1 shows a third generation GPRS network part (3G-GPRS) in the UMTS and the respective corresponding GPRS components.
Packet data are for example sent from an external network such as the Internet (or the PSTN=Public Switched Telephone Network) to a terminal device of a user such as a mobile station MS (downlink DL transmission), or vice versa (uplink UL transmission). The subsequent brief explanation of packet data transmission will now refer to the downlink DL transmission.
The connection between the UMTS (GPRS part) network UMTS and the external network is established via a so-called 3G-GGSN (=3rd generation Gateway GPRS Support Node). The 3G-GGSN as a network element transfers the received data via a 3G-SGSN (=3rd generation Serving GPRS Support Node) (this is optionally, since a GGSN may also act as a SGSN in future UMTS standards releases, although at present a SGSN is mandatory) to a (radio) network controller device RNC (in UMTS; corresponding to a base station controller BSC in GPRS) adapted top control a (radio) access network consisting of at least one Node B (in UMTS) (which corresponds to a base transceiver station BTS in GPRS) (in case of a radio access network). The access network then accesses and communicates with the user's terminal MS.
In downlink DL, the RNC controls the forwarding of data packets to the mobile station as the destination, while in uplink the GGSN controls the forwarding of data packets to the external network as the destination.
When forwarding such data packets via the packet data network such as a GPRS network, the provisioning of a sufficient quality of the service i.e. the transmission of data packets, is essential. This is referred to as QoS.
Provisioning of QoS in GPRS phase 1 could not be successfully established. In a subsequent GPRS phase 2, and therefore also in a UMTS network, data packets can be transmitted using different transmission protocol types. For example, the following protocol types are supported: UDP (User Datagram Protocol), mostly used for real time applications; TCP (Transmission Control Protocol), PPP (Point to Point Protocol), X.25 protocol, IP (Internet Protocol), OSP:IHOSS (Octet Streaming Protocol:Internet Hosted Octet Streaming Service).
All of these PDP types underlie respective different requirements. Also, different applications (e.g. real-time applications and/or non-real time applications) can be run on top of the PDP contexts of the above mentioned PDP types. However, different applications will require a respective different service from the network.
For example, the X.25 protocol requires the data packets to be sent reliable and delivered in-order, i.e. in the same sequence as they were initially transmitted/forwarded. PPP protocol, on the other hand, requires a less reliable transmission, i.e. some data packets can be lost without significantly affecting QoS, but the data packets not lost have to be delivered in-sequence. Still further, IP protocol based transmissions do neither have to preserve the order of the sent packets nor to be reliable in the sense that no data packets are to be lost.
For this purpose, a delivery order attribute as a PDP context QoS parameter has recently been defined. To be included in a set of UMTS bearer QoS parameters. These parameters are still subject to a non-concluded standardization process. A delivery order attribute is defined in 3GPP, Technical Specification Group Services and System Aspects, QoS Concept (3G TR 23.907; May 1999, Version 1.1.0).
The delivery order attribute parameter (DOA) defines for UMTS if the order of transmitted packets has to be maintained or not. In case the order is to be maintained, this leads to the necessity of a node or network element of the network (GPRS comparable part of UMTS) to rearrange the received (disordered) data packets to thereby reconstruct the initial sequence of the data packets as they were sent.
However, this additional parameter is hard to define by an end-user who can be expected not to be an expert in telecommunication networks. Namely, such a “normal” end-user presumably does not know whether such a property (of in-order packets) is necessary for an activated service and/or how the property affects the operation.
Moreover, in order to support different applications on top of the UMTS bearer, four traffic classes have been developed. Namely, a conversational, streaming, interactive and background traffic class, respectively.
PDP types mentioned above are independent of the traffic classes. Stated in other words, each PDP type (protocol type) may run over several traffic classes. In addition, the selection of traffic class sets some requirements for the handling of the prevailing traffic in terms of scheduling and/or buffering of transmitted data packets. Also, a delivery order is defined in each traffic class, but this is currently not in line with the requirements imposed to the traffic classes. Further prior art is known from document WO 97/22201.